A new report from Europe raises serious alarms about orbital collisions

“I think we are going to lose the ability to use certain orbits.”

Eric Berger ars TECHNICA, – Sep 23, 2026

The 2013 sci-fi blockbuster film Gravity, starring Sandra Bullock and George Clooney, popularized the notion of the Kessler syndrome. In the movie, Russia shoots down a defunct satellite and creates a cloud of debris, leading to serious tension in orbit.

The movie is fantastic, a true thriller, and while some liberties were taken with the depiction of outer space, the basic premise of a cascading series of collisions rendering orbits too cluttered with debris to be usable is valid. The idea was first proposed by NASA scientists Donald Kessler and Burton Cour-Palais nearly half a century ago.

Still, the movie was science fiction, right?

Well, a lot has changed since Gravity‘s release. At the time that theatergoers were sitting on the edges of their seats and watching Bullock dodge debris, there were only about 1,000 active satellites in orbit. Today, that number is closer to 17,000, according to CelesTrak.

The preponderance of this growth has been driven by SpaceX’s Starlink constellation, which now has approximately 11,000 satellites in orbit, with many thousands more on the way. And SpaceX is not alone in the race to provide Internet from space. Amazon has launched hundreds of satellites, with thousands more to follow. Multiple Chinese Internet constellations are likewise in progress.

Then there are the orbital data centers, which may produce hundreds of thousands of satellites.

We’ve written a lot about these constellations, and they have generated a bunch of questions. Most prominent among them: Just how sustainable is all of this? Will we see the Kessler syndrome play out in real time? Here are some answers.

How bad is the situation?

It depends on who you ask, so let’s start with the glass-half-empty and glass-half-full outlooks.

Starting with the pessimists: A few years ago, one of the world’s experts in orbital debris, University of Texas at Austin professor Moriba Jah, told Ars that he worries a lot about the consequences of satellites and debris in low-Earth orbit.

“I think we are going to lose the ability to use certain orbits because the carrying capacity is going to get saturated by objects and junk,” Jah said. ” I also predict that we will see a loss of human life by (1) school bus-sized objects reentering and surviving reentry and hitting a populated area, or (2) people riding on this wave of civil and commercial astronauts basically having their vehicle getting scwhacked by an unpredicted piece of junk. I predict that both those things are going to happen in the next decade.”

At the other end of the spectrum is the person almost solely responsible for the remarkable growth in satellites over the last decade, SpaceX founder Elon Musk. His attitude has largely been that space is big, and things will probably be just fine. For example, during a SpaceX-produced interview this summer at the company’s Starlink terminal factory in Bastrop, Texas, Musk said, “Space is really big. It’s not like space is gonna get crowded. Space is enormous. If you actually look at it relative to the Earth, the satellites are so tiny you can’t even see them.”

So in one way of thinking, very, very bad things are coming. In another, everything’s fine. Where does the truth actually lie?

What’s really happening?

One of the most credible sources for this kind of information is the European Space Agency, which has long studied space debris and its impacts on various orbits.

Fortunately, it just released its annual Space Environment Report a week ago. The European agency has produced such a report over the last decade to provide a transparent overview of global space activities and assess the quality of efforts to preserve the sustainability of spaceflight.

There are some striking—and concerning—changes this year. For example, the European report has dramatically increased its projections of future satellites in this year’s report after reassessing the current trajectory of large constellations.

“The notable increase in the index this year is primarily driven by the substantially larger future population resulting from the current extrapolation scenario,” the report states. “In particular, the growing influence of large constellations highlights the limitations of traditional mitigation approaches when applied to future traffic at unprecedented scales. At the same time, the results are affected by the limited availability of detailed and verifiable information on future deployment plans, operational practices, and end-of-life strategies of these systems.”

More satellites mean an increasing probability of collisions, which helps to push us toward a Kessler-like scenario…………………………………………………………………………………………………………………………………………………………………. https://arstechnica.com/space/2026/09/there-are-now-17000-satellites-in-orbit-and-growing-should-we-be-concerned/